Blue Whale

We think of dinosaurs as being really big, and many of them were. However, the largest animal that has ever lived is alive today.

The blue whale is about 100 feet (30 meters) long and can weigh 190 tons (170 metric tons). That is the weight of about 2700 people! The blue whale’s tongue weighs as much as an elephant. At birth, a blue whale calf weighs as much as a full-grown hippopotamus. Blue whales have a heart that weighs 400 pounds (180 kg).

Imagine a diet of one million calories a day! Considering the size and calorie requirements of a blue whale, you might think this animal would have a difficult time just surviving. Even more amazing is that their diet is almost exclusively tiny sea creatures called krill. In spite of all those factors, the blue whale life expectancy is 120 years!

The blue whale is considered to be an endangered species, but not for natural causes. Because of their enormous size, they have virtually no predators even though sometimes groups of orcas attack them. The big problem for blue whales has historically been humans. Human whalers took an enormous toll until hunting blue whales was outlawed in the 1960s and finally ended in the 1970s. Even today they are sometimes killed by collisions with ocean vessels or by being tangled in fishing nets.